Imagine it is 1965: you are asked which of Britain’s two recently arrived migrant populations will integrate more readily. Your first reaction might be to review recent evidence. Caribbeans come from Christian backgrounds, speak English and are familiar with many British institutions, including an educational system they venerate. In this sense, they need no cultural street guide. The landscape for South Asians is unfamiliar, perhaps even forbidding. Many do not speak English, have no places of worship, or shops from where they can buy their favoured food. Some dress in ways that attract stares. They look set to become an anomalous presence.You resume your accounting 20 years later and, to your surprise, a seemingly permanent underclass of unemployed Caribbeans is now, as research indicates, trapped in a downward spiral of underachievement at school, followed by crime and imprisonment. The stability of the family appears under threat, Christianity is being challenged by the rise of Rastafari and disintegration looks likely. Brixton, Handsworth and other inner-city areas are ablaze, as young blacks serve notice of a crisis.

South Asians, meanwhile, have diffused into commerce, built their own places of worship, worked their way into higher education and are slowly, but cumulatively progressing into the professions. You have to reckon with a kind of Law of Rebounding Returns: every time, they encounter a rebuff, Asians bounce back with renewed determination. While the achievers are held up as exemplary minorities, the lesser-achieving mortals draw scant approval, and even then only for their non-confrontational response to their predicament.Another 20 years: evidence in 2005 further complicates matters. Britons of Indian descent vie with the much smaller Chinese population as the country’s educational high-performing elite, while others, in particular Pakistanis and Bangladeshis (90 per cent of whom are Muslims), struggle in both education and in the desirable professions. There is talk of voluntary segregation, but for the most part British Asians, as they are now called, have ticked all the boxes of integration. Well, almost all of them: a bomb attack in London suggests a rage among some sectors of the population. It triggers retaliatory violence reminiscent of the 1970s, only this time called Islamophobia (though the violence seems to be directed to anyone who appears to be of Asian origin, regardless of faith). Arson raids on mosques and Asian-owned shops become commonplace. Imams are habitually assaulted and hate crimes against Asians contribute to a climate of perplexity and fear.A few days ago British Prime Minister David Cameron declared: “Adhering to British values is not an option or a choice.” Cameron also announced his government will consider “specific and discretionary” powers that would prevent British terrorist suspects from returning to the UK. At least 500 British nationals, mostly of Asian background or descent, have fled their home country to fight in bloody conflicts in Iraq and Syria alongside extremist groups. Radicalization is the term we use to describe their conversion to the worldview offered by Islamic State, or IS, the Sunnijihadist group that claims authority over all Muslims and claims to be establishing a caliphate, or Islamic state, on the territories it controls in Iraq and Syria. Britain is not alone: several western nations, including France, Germany and the USA, have seen citizens enthusiastically adopting the IS ideology. Recent studies show how British Muslims feel victimized by discriminatory policing, sentencing and negative media reporting. This perception informs a self-understanding as a deviant presence. So, when young Muslims become aware that, since September 11, 2001, there has been what some understand as a progressive attempt to destroy Islam, they relate their own experiences vicariously to the global situation. The hostilities in Iraq, Afghanistan, Syria, Palestine and elsewhere shape their awareness, suggesting that the worldwide conflict between Muslims and non-Muslims affects the mindset of young people physically removed from the actual conflict. The so-called ‘war on terror’ is imagined as a war on Muslims in the eyes of some British Asians.The global conflict provides a schema — a plan or outline that helps make sense of the world. Believing you are the victim of oppressive, prejudicial policing makes sense if you accept that you are part of an unjust exercise of force that forms a wider pattern. Some have suspected that the renewal of Muslim identity is the effect rather than the cause of conflict in Britain, though there is evidence that forms of allegiance focused on place, nationality, class or profession appear to lack an encompassing worldview and are less persuasive that the most powerful and reaffirming outlook offered by IS. At a different time in history, the behaviour of some young British Asians might be symptomatic of their estrangement from a society in which their access to education, political positions or high-ranking jobs was restricted by institutional racism. These would have been citable reasons in the 1980s, but not in the twenty-first century. Something truly incredible is going on.Some young Muslims have linked their own situation to a global struggle. Radicalization is not the result of brainwashing, but of re-socialization: experiences of racism and exclusion have weakened the plausibility of the vision of the world offered by the parents and others. Cognitively and affectively young Muslims have switched focus to an alternative conception in which the world is divided starkly between Islam and all others. Cameron’s measures to withdraw passports, citizenship and “de-radicalize” are well-intended, but misunderstand the fundamental causes of the radicalization of Muslim youth: it is right here on the streets of Britain, in the everyday interaction of young Asians. The crisis may be in Syria and the middle-east; its roots lie in places like London, Birmingham and Manchester. @elliscashmore